Accumulated Other Comprehensive Loss - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2013
Comprehensive Income (Loss) [Line Items]
Amount reclassified from accumulated other comprehensive loss net periodic cost for amortization of loss of defined benefit Pension Plan	$ 97

Net of tax amount of the income statement impact of the reclassification adjustment for prior service costs recognized as a component of net period benefit cost.

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+ Details